Louis percy sefton



(No Model.) I

' L. P. SEPTON.

SHARPENER FOR-REAPBR AND MOWER BLADES.

Patented Mar. 13, 1888.

WITNESSES:

- UNITED STATES PATENT OFF CE.

LOUIS PERCY SEFTON, OF TORONTO, ONTARIO, CANADA.

SHARPEN ER FOR REA PER AND MOWER BLADES.

SPECIPICA'I'IQN forming part of Letters Patent No. 379,335, dated March13, 1888.

Application filed October 8, 1887. Serial No. 251,818. (No model.)Patented in Canada July 22, 1887, No. 27,230.

To aZZ whom it may concern.-

Beit known that I, LOUIS PERCY SEFTON, a citizen of the United States,now residing in Toronto, in the Province of Ontario and Dominion ofCanada, have invented a new and Improved Sharpener for Reaper and MowerKnives, (for which Letters Patent have been granted me in the Dominionof Canada, No. 27,230, dated July 22, 1887,) of which the following is afull, clear, and exact description.

My invention relates to an improvement in sharpening reaper and mowerknives, and has for its object to provide an improved device forsharpening the blades or knives of reapers and mowers without removingthem from the machine.

The invention consists in the construction and combination of theseveral parts, as will be hereinafter fully set forth, and pointed outin the claims.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figure 1 is a plan view of the device. Fig. 2 is a horizontal sectionthereof. Fig. 3 is an end view, and Fig. 4 is a transverse section.

The body A and handle 0 of the sharpener are formed integrally from acomposition whose chiefingredient is emery by subjecting it to heavypressure in a mold. A steel-wire link,

D, is embedded longitndinallyin the said body A and handle 0 at the timeof molding, for the purpose of imparting a certain requisite degree ofstiffness or rigidity and to prevent the parts becoming disconnected incase they should be cracked or broken. The link has a further advantageover a plate or flat bar of like strength, in that it offers lesssurface to prevent cont-act and cohesion of the emery composition.

I The body A ofthc sharpener is approximately diamond-shaped incross-section, each side thereof sloping inward each way from a centrallongitudinal line, thus forming the two fiat surfaces B. These twoopposite surfaces B B (on either side of body A) form an obtuse anglewith each other, and if continued would form an acute angle with each ofthe opposite fiat surfaces B on the other side of the body A; butinstead ofsuch angle beingformed the juncture of the said surfaces isformed by a curved line. In other words, the edges ofthe body A whichare farthest apart are curved or rounded in place of being made sharp.The reason for this construction is that the curved edge will not breakor chip in ordinary use, but always present a smooth even surface,whereas a sharp edge soon becomes notched or ragged, so that the devicecannot be used successfully, as before, and sooner becomes worn out andworthless for its intended purpose.

Experiment has demonstrated that the form and composition of thissharpener enable it to be used with entire success for sharpening knivesof mowing-machines in the field, thus saving the most'of the time,labor, and expense which would be involved in detaching the knife-barand carrying it off the field to be ground.

What I claim is- 1. As a new article of manufacture, the improvedsharpener for mower-knives, the same being composed of the body A,having an approximately diamond shape in crosssection, such body and thehandle 0 being formed integrally from a composition whose chiefingredient is emery, and the link-stiffener D, embedded in the devicelongitudinally, as shown and described.

2. The mower-knife sharpener consisting of an internal metal stiffener,and the body A and handle 0, both formed from an emery composition, thesaid body being approximately diamond shaped in cross-section and havingthe opposite edges which are farthest apart curved, as shown, for thepurpose specified.

LOUIS PERCY SEFTON.

Witnesses:

E. R. CHILLAS, B. J. THORNE.

